One obvious noun for "the state of being flustered" is ... flustration. Writing in the late nineteenth century, Farmer & Henley, in Slang and Its Analogues (1893), list it as being "old and colloquial":

[Example] 1848. Jones, Studies of Travel, p.21. "The old woman was in such a flustration that she didn't know her lips from anything else."

[Example] 1872. Mortimer Collins, Two Plunges for a Pearl, vol. II, ch. vii. "Then was this pretty little actress whom he admired in a great state of flustration."

The word remains in use today, but it has never escaped the ignominy of being excluded by, for example, the Merriam-Webster's Collegiate Dictionary series. Owing to its status as a word not in good standing, it can be damaging to the credibility of people who use it in serious writing—people like Martin Loosemore, in his book, Crisis Management in Construction Projects (2000):

When parties abuse their illegitimate power, weaker parties, who may be in the right, suffer unduly. This causes malevolence, flustration, and the potential for conflict. Try to ensure fairness in the bargaining process.

What then, can we conclude about the politics of public utility regulation? It is a visible process that frustrates participants who lack political support. It is a technical process that frustrates participants who lack expertise. It is an expensive process that frustrates participants who lack resources. It is a controversial process that frustrates participants who make authoritative decisions. In the patois of the deep South, the politics of public utility regulation is the politics of "flustration."

It may be tempting to read flustration here as being simply a regionalism for frustration, but I think it is perhaps more accurately viewed as an amalgam of two notions: being frustrated and being flustered.

If you fear the ill effects of using flustration (and I certainly would), you might opt instead for pother, which Merriam-Webster's accepts as being a word above suspicion, and which means much the same thing as flustration, to judge from its entry in the Eleventh Collegiate Dictionary (2003):

Why would one use flustration instead of the simpler fluster? I’m trying to think whether there is some difference between them. Your most recent citation (2000) almost looks like an error for frustration.
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tchristApr 18 '14 at 1:51

I upvoted your answer, tchrist, because fluster is an even more obvious noun than flustration (or pother); nevertheless, I can't recall ever having heard a person say, "I'm in a fluster." Perhaps most people tend to avoid using a noun form for this state, and build around the verb fluster or the adjective flustered instead. I can think of three reasons why a person might prefer flustration to other options: They like its colloquial tone; they like the echo of "frustration" that attends it; or it's the normal word that people around them use to describe the state of being flustered.
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Sven YargsApr 18 '14 at 2:13

Don't use "pother" if you expect all English-speakers to recognise it though. It's obscure. Not that rarity is the same thing as obscurity, but: books.google.com/ngrams/…
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Steve JessopApr 18 '14 at 11:40

@SvenYargs: someone doing a camp comedy act would say "oooh, I'm all in a fluster" at the drop of a hat. I feel like I'd be more likely to hear it in conversation from my grandparents than my peers, but I can't back that up with anything.
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Steve JessopApr 18 '14 at 11:44

I am shocked that flustration is over 10 years old. I would have thought for sure it would be a recent neologism.
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Patrick MApr 18 '14 at 15:53

I don't think the forms of the words you've represented here would be usable; I suspect OP is attempting to use a possessive form i.e. In his flusteredness [sic]". I think you would agree that none of the forms of the words you have here are applicable
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kolossusApr 17 '14 at 21:42